hey steve. Im working with 2 15's. Each pushing 2,000 RMS. Right now im trying to just stay with batteries and then eventually go with an alternator. I want to get XS power batts but dont know which kind or how many. Please help bro. Im out of Vacaville CA. Im in the USAF at Travis AFB. I really need help with these batts cause i wanna get it right the first time. I have a 2006 Dodge Magnum. Thanks Again